well,
I think he should've had spare strings, or a spare axe..
Exactly. As Craig said, it takes 10-15 seconds to swap, I've swapped during songs with bands that didn't know to keep playing and they still kept playing, fortunately.
I keep 6 electrics onstage and the acoustic and usually my lap steel. 3 in standard tuning, one drop D, one open G, one open D. If drop D happens to break a string (very rare, I change strings every gig for guitars with whammy bars, every other gig for those without) I can retune the Cort to drop D in a few seconds.
I prefer to always keep it to 20 seconds or less between songs, I can swap guitars in 10 seconds every time, been doing it for years.
Interesting anecdote, slightly off topic, onstage one night, first set, had trouble getting decent sound and any volume. My best friend was there, she usually is, I had her (during a song) grab a spare guitar cable and set it beside my guitar rack. Between songs I ran it to the volume pedal, bypassed all other effects and wireless, straight into the Super Reverb. Played out the rest of the set with no trouble.
Between sets I started troubleshooting, add one thing at a time, and of course the last item, the wireless, was the problem. I had forgotten to turn up the output volume before I started, it was sending almost no signal at all...made me feel like an idiot, but if I hadn't had a spare guitar cable I would have been forced to either run without my volume pedal (a fate worse than death for me) or troubleshoot while everyone waited...out of the question...
So yeah, I bring spare everything, I'd bring a spare equipment truck if I could...
I think you were right to fire the guy, sounds like he was just a wannabe. I play as little as possible before the show, just enough to get my tone and effects dialed in, and just doodles, never any recognizable songs. Volume leval can wait till the sound check. I never doodle onstage between songs either, I'd bet this guy did plenty of that too.
Borrowing a guitar from another band is just a bad idea. I borrowed an amp from another band, the guy offered so I said ok, at a battle of bands in Port Arthur Texas, 1973. He pulled the plug halfway through our second song, got us shut down pretty quick. I found out later he had seen us before and knew we would blow his band right out of the water so he sabotaged us. We should have made it to top 3 at least...
I never borrowed from another band again except for an opening gig for 4th of July in Baton Rouge, I was plenty worried but that one worked out great, we were using the other band's entire setup, again they offered, so we wouldn't have to haul all our gear for a one hour show. It went really well that time and the band we opened for loved us, they had never heard us but had heard of us, and we had a great reputation, that's why they asked us to open the show. I think they told us 3 other bands recommended us when they couldn't make it for other commitments.